Low skeletal muscle mass as predictor of postoperative complications and decreased overall survival in locally advanced head and neck squamous cell carcinoma: the role of ultrasound of rectus femoris muscle.

PURPOSE Skeletal muscle mass (SMM) depletion and sarcopenia as predictors of postoperative complications and poorer overall survival (OS) have been validated in many surgical fields through cross-sectional imaging (CT, MRI), with potential limitations. We evaluated it in a stage III-IV head and neck squamous cell carcinoma (HNSCC) surgical cohort through ultrasound (US) of rectus femoris muscle (RF), a quick, cheap, repeatable alternative. METHODS Patients submitted to surgical treatment with curative purpose were recruited and prospectively evaluated through clinical, biometric, biochemical, surgical, pathological and functional prognosticators and with preoperative US of RF with regards to 30-day complications and OS. RESULTS Forty-seven patients completed the study. RF cross-sectional area (RF-CSA) was used to identify patients with low SMM (CSA ≤ 0.97 cm2: 18/47, 38.3%). RF-CSA was lower in complicated cases (0.95 ± 0.48 vs 1.41 ± 0.49 cm2; p = 0.003), remaining the only independent predictor of postoperative complications at multivariate analysis, with a model including ASA score and modified Frailty index (OR 9.84; p = 0.004). SMM depletion significantly impaired OS (13.6 ± 2.9 vs 26.3 ± 2.1 months; p = 0.017), being its only independent prognosticator at multivariate Cox regression analysis (OR 4.42; p = 0.033). CONCLUSION RF-CSA, evaluated with US, seems a reliable method for identification of patients with low SMM in a stage III-IV HNSCC cohort, defining a subset at high-risk of 30-day complications and poorer OS.